(276,’2007-03-10 22:40:51′,’david’,’2007-03-10 22:40:51′,”,’CNC 8×12 Lathe Z-Axis Prototype’,”,’Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8″ x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

After drilling out the four rivets that hold the plate to the bed end, we end up with, well, the end of the bed with the plate removed:

If you’ve seen us mocking up prototypes before, you’ll remember that we find the use of index cards, hot-glued cardboard, wood, and other easily-cut materials ideal for quick mock-ups.

After we roughly determined the length of the ballscrew, motor mounting plate (for both NEMA 23 and 34 framed motors), we began turning the ballscrew.

Here we’ll digress for a few moments and discuss how we’ve slowly converted to grinding our own HSS (high speed steel) tool bits instead of using carbide inserts. One of the immediate differences you’ll notice when using HSS over inserts is not only the cost savings, but that it really only takes less than a minute to create a suitable cutting tool for turning. For us, as we turn lots of ballscrews and ACME leadscrews, we’ve never found the inserts and these benchtop lathes to be ideal mates. Turning hardened alloys and even free-machining steels has always posed challenges when trying to produce a smooth finish that can be accomplished with just a few passes of fine grit sandpaper after a HSS bit-cut. We can even make a nice cutting tool for peeling away .050″ DOC of aluminum that still leaves quite a nice finish!

We’ll skip the usual clips of turning ballscrews turning at a lowly 240 RPM (it produced nice chips with no change in color – not even straw) and show you the final result of the shaft end with the 5/16″ bit used:

We didn’t use a post-process like wet sanding and the finish is smooth. We could polish it from here, but it’s not necessary. Here’s the front relief:

And the side relief:

As you can see, all you need are the top, side, and front reliefs at roughly 5 degrees or so, making sure that you take into account the direction of cut (tailstock to headstock or vice versa). You can spend less than a minute (we did) and end up with a bit that doesn’t look all that great but performs beautifully.

Back to the CNC conversion. We’re going to keep manual function of the lathe, so the CNC will be something you can switch over to for repetitive processes (like turning down leadscrew bearing journals).

The basic procedure will be to mount the ballnut to the underside of the carriage apron and have the bearing block and shaft to the tail end of the bed:

Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8″ x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

Stay tuned…’,’

Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8” x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

After drilling out the four rivets that hold the plate to the bed end, we end up with, well, the end of the bed with the plate removed:

If you’ve seen us mocking up prototypes before, you’ll remember that we find the use of index cards, hot-glued cardboard, wood, and other easily-cut materials ideal for quick mock-ups.

After we roughly determined the length of the ballscrew, motor mounting plate (for both NEMA 23 and 34 framed motors), we began turning the ballscrew.

Here we’ll digress for a few moments and discuss how we’ve slowly converted to grinding our own HSS (high speed steel) tool bits instead of using carbide inserts. One of the immediate differences you’ll notice when using HSS over inserts is not only the cost savings, but that it really only takes less than a minute to create a suitable cutting tool for turning. For us, as we turn lots of ballscrews and ACME leadscrews, we’ve never found the inserts and these benchtop lathes to be ideal mates. Turning hardened alloys and even free-machining steels has always posed challenges when trying to produce a smooth finish that can be accomplished with just a few passes of fine grit sandpaper after a HSS bit-cut. We can even make a nice cutting tool for peeling away .050” DOC of aluminum that still leaves quite a nice finish!

We’ll skip the usual clips of turning ballscrews turning at a lowly 240 RPM (it produced nice chips with no change in color – not even straw) and show you the final result of the shaft end with the 5/16” bit used:

We didn’t use a post-process like wet sanding and the finish is smooth. We could polish it from here, but it’s not necessary. Here’s the front relief:

And the side relief:

As you can see, all you need are the top, side, and front reliefs at roughly 5 degrees or so, making sure that you take into account the direction of cut (tailstock to headstock or vice versa). You can spend less than a minute (we did) and end up with a bit that doesn’t look all that great but performs beautifully.

Back to the CNC conversion. We’re going to keep manual function of the lathe, so the CNC will be something you can switch over to for repetitive processes (like turning down leadscrew bearing journals).

The basic procedure will be to mount the ballnut to the underside of the carriage apron and have the bearing block and shaft to the tail end of the bed:

Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8” x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

Stay tuned…

‘,’Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8″ x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

‘,’

Finally, we’ve resumed posting some pictures of progress we’re making on the CNC 8×12 mini-lathe.

We had mocked up some placements of the cross-feed ballscrew a while back. Today, we’ll work on the Z-axis. First things first, we’ll get started on the 5/8” x 5 TPI ballscrew. All that’s needed is to turn down the rough lengthed bearing journal, thread, and shaft coupling length.

The basic concept is to mount a plate on the back end of the bed where the “Induction Hardened Bedways” label is attached.

‘,”,’8x128x14-Small-Lathe’,”,1,’Comment’,0,4,1,1,’article’,”,”,’cnc-8×12-lathe-z-axis-prototype’,”,”,”,”,”,”,”,”,”,”,’796a21f4602b39d10de920a4f90adbc5′,’2007-03-10′);

(275,’2007-03-10 21:46:05′,’david’,’2007-03-13 07:45:19′,’david’,’Cast Iron Bed Mounted – X and Y Axes Almost Completed’,”,’We’ve been working on the home-brewed CNC vertical mill lately. The latest development was the installation of the cast iron T-slot table.

While not the ideal table width, the depth of just over 6″ makes it heftier than the X2 mini-mill base (though not as wide). Eventhough the base isn’t as wide as the mini-mill’s, with the travel this mill has, makes that dimension only important in that we can’t clamp the workpiece to the table should it reach a size of 6″ x 12″.

We’re pretty happy with many Phase 2 products such as their line of QCTPs for the mini-lathe, but their X/Y table is just about the worst quality piece of tooling we’ve ever purchased. It took only a quick glance at the table to realize that sacrificing the table wouldn’t cause any heartburn.

As an FYI, the part number is 260-512PHSII “Compound Slide Mill and Drill Table” (ENCO part number 201-2826 often on sale for $70). From the moment we took delivery of this table, one of gib set screws broke as we tried to tighten it. The backlash on the leadscrews is the worst we’ve ever experienced. The bottom line is that the only salvagable part is the cast iron table.

The first thing we had to do was to recess the holes in the aluminum base plate so that the cast iron table could sit flush on it. Since we now have a Kurt D675 vise that has a jaw opening of over 7″ and a RF-31 clone mill/drill with 7″ Y travel, we felt confident that we could not only chuck the base plate in the vise, but also with the extended work envelope of the mill/drill, could easily in one pass perform the 1/2″ diameter 4-flute end mill recesses to accept the button head socket screws. Unfortunately, the Kurt D675 has a rather large base which prevented us from doing so..

As you can see from the above picture, the end of the base hits the column of the mill just at around 5″ of travel. This vise is better suited for a full-sized knee mill (or the home-brewed mill we’re working on ).

Next up, we had to drill and tap a series of holes on the underside of the cast iron table, mill away at the support for the leadscrew, and drill and tap holes in the offset spacer rails that sit between the bottom of the table way and the aluminum base plate:

Even without a DRO, the .001″ increment hand dials made keeping track of positioning much easier than with the .0125″ increments found with many Asian mini machinery.

Here we begin assembling the base plate to the linear bearing blocks:

Then we mount the spacer rails to the table and then the base plate:

Now onto the Z-axis column…

Or, start from the beginning.’,’

We’ve been working on the home-brewed CNC vertical mill lately. The latest development was the installation of the cast iron T-slot table.

While not the ideal table width, the depth of just over 6” makes it heftier than the X2 mini-mill base (though not as wide). Eventhough the base isn’t as wide as the mini-mill’s, with the travel this mill has, makes that dimension only important in that we can’t clamp the workpiece to the table should it reach a size of 6” x 12”.

We’re pretty happy with many Phase 2 products such as their line of QCTPs for the mini-lathe, but their X/Y table is just about the worst quality piece of tooling we’ve ever purchased. It took only a quick glance at the table to realize that sacrificing the table wouldn’t cause any heartburn.

As an FYI, the part number is 260-512PHSII “Compound Slide Mill and Drill Table” (ENCO part number 201-2826 often on sale for $70). From the moment we took delivery of this table, one of gib set screws broke as we tried to tighten it. The backlash on the leadscrews is the worst we’ve ever experienced. The bottom line is that the only salvagable part is the cast iron table.

The first thing we had to do was to recess the holes in the aluminum base plate so that the cast iron table could sit flush on it. Since we now have a Kurt D675 vise that has a jaw opening of over 7” and a RF-31 clone mill/drill with 7” Y travel, we felt confident that we could not only chuck the base plate in the vise, but also with the extended work envelope of the mill/drill, could easily in one pass perform the 1/2” diameter 4-flute end mill recesses to accept the button head socket screws. Unfortunately, the Kurt D675 has a rather large base which prevented us from doing so..

As you can see from the above picture, the end of the base hits the column of the mill just at around 5” of travel. This vise is better suited for a full-sized knee mill (or the home-brewed mill we’re working on ).

Next up, we had to drill and tap a series of holes on the underside of the cast iron table, mill away at the support for the leadscrew, and drill and tap holes in the offset spacer rails that sit between the bottom of the table way and the aluminum base plate:

Even without a DRO, the .001” increment hand dials made keeping track of positioning much easier than with the .0125” increments found with many Asian mini machinery.

Here we begin assembling the base plate to the linear bearing blocks:

Then we mount the spacer rails to the table and then the base plate:

Now onto the Z-axis column…

Or, start from the beginning.

‘,’We’ve been working on the home-brewed CNC vertical mill lately. The latest development was the installation of the cast iron T-slot table.

While not the ideal table width, the depth of just over 6″ makes it heftier than the X2 mini-mill base (though not as wide). Eventhough the base isn’t as wide as the mini-mill’s, with the travel this mill has, makes that dimension only important in that we can’t clamp the workpiece to the table should it reach a size of 6″ x 12″.

We’re pretty happy with many Phase 2 products such as their line of QCTPs for the mini-lathe, but their X/Y table is just about the worst quality piece of tooling we’ve ever purchased. It took only a quick glance at the table to realize that sacrificing the table wouldn’t cause any heartburn.

As an FYI, the part number is 260-512PHSII “Compound Slide Mill and Drill Table” (ENCO part number 201-2826 often on sale for $70). From the moment we took delivery of this table, one of gib set screws broke as we tried to tighten it. The backlash on the leadscrews is the worst we’ve ever experienced. The bottom line is that the only salvagable part is the cast iron table.

\r\n’,’

We’ve been working on the home-brewed CNC vertical mill lately. The latest development was the installation of the cast iron T-slot table.

While not the ideal table width, the depth of just over 6” makes it heftier than the X2 mini-mill base (though not as wide). Eventhough the base isn’t as wide as the mini-mill’s, with the travel this mill has, makes that dimension only important in that we can’t clamp the workpiece to the table should it reach a size of 6” x 12”.

We’re pretty happy with many Phase 2 products such as their line of QCTPs for the mini-lathe, but their X/Y table is just about the worst quality piece of tooling we’ve ever purchased. It took only a quick glance at the table to realize that sacrificing the table wouldn’t cause any heartburn.

As an FYI, the part number is 260-512PHSII “Compound Slide Mill and Drill Table” (ENCO part number 201-2826 often on sale for $70). From the moment we took delivery of this table, one of gib set screws broke as we tried to tighten it. The backlash on the leadscrews is the worst we’ve ever experienced. The bottom line is that the only salvagable part is the cast iron table.

‘,”,’Home-Brewed-CNC-Vertical-Mill’,”,1,’Comment’,0,4,1,1,’article’,”,”,’cast-iron-bed-mounted-x-and-y-axes-almost-completed’,”,”,”,”,”,”,”,”,”,”,’f0a6bb1b90e1df1d3738bed871a8266b’,’2007-03-10′);

(274,’2007-02-20 17:58:37′,’david’,’2007-02-20 18:06:47′,’david’,’Kurt D675 AngLock Vise Arrived!’,”,’We started machining small parts. As we moved onto larger machines and workpieces for making things for the small mini-machines making things for those machines (say that 10 times ), we needed to become more efficient in some operations. We’ve always been big fans of workholding techniques. Having a large vise is just part of that fascination.

When we moved onto the ever-popular round-column mill/drill with a table that rivals that of full-sized knee/turret mills (9″x32″ table to be exact), we were in need of a larger vise. The choice was simple – a 6″ wide vise that you commonly find in many machine shops. Instead of buying an import this time, we wanted to buy real American cast iron. The Kurt D675 was the obvious choice.

After checking out ENCO and few other catalogs, we found a good deal via eBay. Even with shipping charges, we were able to save some money.

A week later, the box arrived:

Another picture of the box (we promise to show something a bit more substantial in a few seconds):

We opened up the box to find the warranty card, a bag containing two o-rings, and the 80 lb. vise.

We then lug the vise out and get a glimpse of the massiveness of the vise:

Flipping the vise over, we see a nice casting with a very prominent “USA” ground in:

The size placard/nameplate and the “Kurt blue” says it all:

They also include what they call a “chip guard”. It’s merely a thin guage sheet steel that slides in between the channel to cover the innards of the vise from chips.

Just for scale, we’ve chucked in the X2 mini-mill belt drive conversion plate lengthwise in the vise:

And the spindle/head of the mini-mill is also placed in there. This is one very hefty piece of American cast iron, indeed!

We’ll post more pictures with this vise mounted in its new home and provide some tips and tricks in workholding at a later time.

In the meantime, you can read more about why we chose the D675 over the D688 and D810 from Kurt as well the Parlec PSW-6900 6″ vise.

Stay tuned…

‘,’

We started machining small parts. As we moved onto larger machines and workpieces for making things for the small mini-machines making things for those machines (say that 10 times ), we needed to become more efficient in some operations. We’ve always been big fans of workholding techniques. Having a large vise is just part of that fascination.

When we moved onto the ever-popular round-column mill/drill with a table that rivals that of full-sized knee/turret mills (9“x32” table to be exact), we were in need of a larger vise. The choice was simple – a 6” wide vise that you commonly find in many machine shops. Instead of buying an import this time, we wanted to buy real American cast iron. The Kurt D675 was the obvious choice.

After checking out ENCO and few other catalogs, we found a good deal via eBay. Even with shipping charges, we were able to save some money.

A week later, the box arrived:

Another picture of the box (we promise to show something a bit more substantial in a few seconds):

We opened up the box to find the warranty card, a bag containing two o-rings, and the 80 lb. vise.

We then lug the vise out and get a glimpse of the massiveness of the vise:

Flipping the vise over, we see a nice casting with a very prominent “USA” ground in:

The size placard/nameplate and the “Kurt blue” says it all:

They also include what they call a “chip guard”. It’s merely a thin guage sheet steel that slides in between the channel to cover the innards of the vise from chips.

Just for scale, we’ve chucked in the X2 mini-mill belt drive conversion plate lengthwise in the vise:

And the spindle/head of the mini-mill is also placed in there. This is one very hefty piece of American cast iron, indeed!

We’ll post more pictures with this vise mounted in its new home and provide some tips and tricks in workholding at a later time.

In the meantime, you can read more about why we chose the D675 over the D688 and D810 from Kurt as well the Parlec PSW-6900 6” vise.

Stay tuned…

‘,’We started machining small parts. As we moved onto larger machines and workpieces for making things for the small mini-machines making things for those machines (say that 10 times ), we needed to become more efficient in some operations. We’ve always been big fans of workholding techniques. Having a large vise is just part of that fascination.

When we moved onto the ever-popular round-column mill/drill with a table that rivals that of full-sized knee/turret mills (9″x32″ table to be exact), we were in need of a larger vise. The choice was simple – a 6″ wide vise that you commonly find in many machine shops. Instead of buying an import this time, we wanted to buy real American cast iron. The Kurt D675 was the obvious choice.

After checking out ENCO and few other catalogs, we found a good deal via eBay. Even with shipping charges, we were able to save some money.

A week later, the box arrived:

‘,’

We started machining small parts. As we moved onto larger machines and workpieces for making things for the small mini-machines making things for those machines (say that 10 times ), we needed to become more efficient in some operations. We’ve always been big fans of workholding techniques. Having a large vise is just part of that fascination.

When we moved onto the ever-popular round-column mill/drill with a table that rivals that of full-sized knee/turret mills (9“x32” table to be exact), we were in need of a larger vise. The choice was simple – a 6” wide vise that you commonly find in many machine shops. Instead of buying an import this time, we wanted to buy real American cast iron. The Kurt D675 was the obvious choice.

After checking out ENCO and few other catalogs, we found a good deal via eBay. Even with shipping charges, we were able to save some money.

A week later, the box arrived:

‘,”,”,”,1,’Comment’,0,4,1,1,’article’,”,”,’kurt-d675-anglock-vise-arrived’,”,”,”,”,”,”,”,”,”,”,’f05e3cb937f8cbc8c4c6f62e8186a370′,’2007-02-20′);